GRUB Error 'invalid environment block' on booting & updating Ubuntu Server 20.04

When I boot my Ubuntu 20.04 server (virtualbox vdi, local dev), I get the following error:

Error: invalid environment block.
press any key to continue....

Now, when I run updates, everything installs correctly, except for grub, which throws this error:

dpkg: error processing package grub-common (--configure):
 installed grub-common package post-installation script subprocess returned error exit status 1
dpkg: dependency problems prevent configuration of grub2-common:
 grub2-common depends on grub-common (= 2.04-1ubuntu26.17); however:
  Package grub-common is not configured yet.

dpkg: error processing package grub2-common (--configure):
 dependency problems - leaving unconfigured
dpkg: dependency problems prevent configuration of grub-pc-bin:
 grub-pc-bin depends on grub-common (= 2.04-1ubuntu26.17); however:
  Package grub-common is not configured yet.

dpkg: error processing package grub-pc-bin (--configure):
 dependency problems - leaving unconfigured
dpkg: dependency problems prevent configuration of grub-pc:
 grub-pc depends on grub-common (= 2.04-1ubuntu26.17); however:
  Package grub-common is not configured yet.
 grub-pc depends on grub2-common (= 2.04-1ubuntu26.17); however:
  Package grub2-common is not configured yet.
 grub-pc depends on grub-pc-bin (= 2.04-1ubuntu26.17); however:
  Package grub-pc-bin is not configured yet.

dpkg: error processing package grub-pc (--configure):
 dependency problems - leaving unconfigured
No apport report written because the error message indicates its a followup error from a previous failure.
No apport report written because the error message indicates its a followup error from a previous failure.
No apport report written because MaxReports is reached already
Errors were encountered while processing:
 grub-common
 grub2-common
 grub-pc-bin
 grub-pc
E: Sub-process /usr/bin/dpkg returned an error code (1)

Solutions I've tried

1. I booted the server from system disk and ran e2fsck /dev/sda2 -y as suggested in Error: invalid environment block. Press any key to continue (Ubuntu 20.04 ZFS), but no luck.

2. Running

   sudo dpkg --configure -a && sudo apt --fix-broken install
   

3. Running

   dpkg --purge --force-depends grub-common && apt-get -f install
   

Any tips?

I don't have enough information, but common things you can always try is:

sudo dpkg --configure -a
sudo apt --fix-broken install

or this:

dpkg --purge --force-depends grub-common
apt-get -f install

or maybe simply this works:

apt update & apt-upgrade